Scoping review of rehabilitation care models for post COVID-19 condition

Abstract Objective To systematically map the current evidence about the characteristics of health systems, providers and patients to design rehabilitation care for post coronavirus disease 2019 (COVID-19) condition. Methods We conducted a scoping review by searching the databases: MEDLINE®, Embase®, Web of Science, Cochrane COVID-19 Registry and Cochrane Central Register of Controlled Trials, from inception to 22 April 2022. The search strategy included terms related to (i) post COVID-19 condition and other currently known terminologies; (ii) care models and pathways; and (iii) rehabilitation. We applied no language or study design restrictions. Two pairs of researchers independently screened title, abstracts and full-text articles and extracted data. We charted the evidence according to five topics: (i) care model components and functions; (ii) safe delivery of rehabilitation; (iii) referral principles; (iv) service delivery settings; and (v) health-care professionals. Findings We screened 13 753 titles and abstracts, read 154 full-text articles, and included 37 articles. The current evidence is conceptual and expert based. Care model components included multidisciplinary teams, continuity or coordination of care, people-centred care and shared decision-making between clinicians and patients. Care model functions included standardized symptoms assessment, telehealth and virtual care and follow-up system. Rehabilitation services were integrated at all levels of a health system from primary care to tertiary hospital-based care. Health-care workers delivering services within a multidisciplinary team included mostly physiotherapists, occupational therapists and psychologists. Conclusion Key policy messages include implementing a multilevel and multiprofessional model; leveraging country health systems’ strengths and learning from other conditions; financing rehabilitation research providing standardized outcomes; and guidance to increase patient safety.


Introduction
People living with post coronavirus disease 2019 (COVID- 19) condition, first described as long COVID, need recognition and rehabilitation. 1 The World Health Organization (WHO) has created a definition for post COVID-19 condition, that is, "history of probable or confirmed [severe acute respiratory syndrome coronavirus 2] infection, usually 3 months from the onset, with symptoms that last for at least 2 months and cannot be explained by an alternative diagnosis. Common symptoms include, but are not limited to, fatigue, shortness of breath and cognitive dysfunction, and generally have an impact on everyday functioning. Symptoms may be new onset following initial recovery from an acute COVID-19 episode or persist from the initial illness. Symptoms may also fluctuate or relapse over time. " 2 A survey of 3762 people with post COVID-19 condition identified that three out of four were still experiencing fatigue, post-exertional symptom exacerbation and cognitive dysfunction after 6 months, and half were unable to fully return to work. 3 Convergent with prospective cohorts, between a third to three quarters of hospitalized and community patients had not recovered at 6 and 12 months and a fifth of patients described persistent functional limitations. [4][5][6][7][8] The multisystemic, fluctuating or episodic and relapsing nature of post COVID-19 condition 9,10 is confirmed by a systematic review of 47 910 patients. 11 A systematic review reporting on 886 388 COVID-19 patients estimated a pooled prevalence of post COVID-19 condition at 43% (95% confidence interval: . 12 As of April 2022, the authors estimated that about 100 million people had or are still living with post COVID-19 condition worldwide. Disabling symptoms affect quality of life, return to work or school, finances and ability to care for self and their families. [13][14][15] The scale of this international public health issue could overwhelm health-care capacity, particularly in low-and middle-income countries.
The multisystemic characteristics of the post COVID-19 condition and its high prevalence cause issues for health systems management, with the need to identify appropriate care models. Innovative post-COVID clinics highlighted the need for continuity of care and multidisciplinary rehabilitation. 11,[16][17][18] Shortcomings are appearing such as long waiting lists, difficulties training clinicians, delivery of safe rehabilita-tion, barriers to access for patients with fatigue, absence of integrated rehabilitation and funding sustainability. 19 The objective of this scoping review is to systematically map the evidence about health system, providers and patients' characteristics to guide decision-makers in designing sustainable rehabilitation care models for post COVID-19 condition.

Methods
The protocol follows the Joanna Briggs Institute guidelines for scoping reviews 20 and the framework from Arksey & O'Malley 21 and Levac et al. 22 We report our review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidelines. 23

Concept and research questions
Rehabilitation is defined as interventions for people with limitations in daily physical, mental and social functioning and aims to help them achieve their optimal level of functioning in their environment. 24 We define a rehabilitation care model as the organizational structure required to deliver rehabilitation interventions within a health system. Care models rely on multiple possible active components required to support the delivery of services. Components also benefit from functions to support the operationalization of the different components that constitute a care model.
Our research question was: what is known about health system, providers and patients' characteristics to design rehabilitation care models for post COVID-19 condition? We explored the two broad concepts of care models and rehabilitation for the specific population of post COVID- 19 condition.
To answer our research question, we defined five topics relevant to decisionmakers (Box 1), which we based on a previous living systematic review on rehabilitation interventions for post COVID-19 condition 26,27 and a rapid systematic review on care models for post COVID-19 condition. 28 Topic 1: what are core components and functions of rehabilitation care in people with post COVID-19 condition? This topic relates to rehabilitation components and functions, which are the active organizational structure required to support the delivery of services and their supporting mechanisms. We present defi-nitions used for proposed components and functions in our data repository. 25 Topic 2: what are conditions for the safe delivery of rehabilitation? This topic relates to the safe delivery of rehabilitation by identifying conditions or symptoms that need management before referral for rehabilitation.
Topic 3: what are the referral principles that need to be considered? This topic relates to identifying relevant patient-level characteristics and criteria and timing for referral into rehabilitation.
Topic 4: in which setting should rehabilitation be provided? This topic relates to describing service delivery setting such as delivery mode, delivery platform, support mechanisms, integration within health system and length of programmes.
Topic 5: what professions need to be involved in the rehabilitation of people with post COVID-19 condition? This topic relates to describing the workforce characteristics required to provide rehabilitation interventions such as common rehabilitation workers, type of competencies and skills, and years of clinical experience.

Eligibility criteria
We included studies of any design meeting the following criteria: (i) studying adult population with post COVID-19 condition (WHO clinical case definition); 2 (ii) reporting on any aspects of rehabilitation care models to answer our defined research questions. We included studies describing complete care models (e.g. pathways, frameworks or structured clinics) and their components and functions, regardless of whether the studies included a comparator or not. Studies reporting any system-level outcomes (e.g. cost-effectiveness, access), provider-level outcomes (e.g. satisfaction, confidence in providing care) or patient-level outcomes (e.g. improved functioning, patient-reported outcome measures, return to work) were eligible.

Search strategy
We systematically searched MEDLINE®, Embase®, Web of Science, Cochrane COVID-19 Registry and Cochrane Central Register of Controlled Trials for studies. An experienced medical information specialist developed and tested the search strategy. The complete search strategy is provided in the data repository. 25 In short, the strategy included terms related to: (i) post CO-VID-19 condition and other currently known terminologies (e.g. post-acute sequelae of COVID-19, long COVID, post COVID-19 syndrome); (ii) care models and pathways (e.g. health-care organization); and (iii) rehabilitation. We built the search string using MeSH terms and free-text terms linked with Boolean collectors (AND, OR, NOT) without any language or study design restriction. Our secondary information sources included a manual search of reference lists or related citations, non-peer reviewed materials including book chapters, governmental agency reports and websites, position papers or proceedings of conferences. In line with the scoping review method, our search strategy was not restrictive and identified citations for our broad aim's main concepts of care models and rehabilitation for post COVID-19 condition.
The search was performed from inception to 24 September 2021 and updated to 22 April 2022. We merged citations from all information sources and we removed duplicates using EndNote version X9 (Clarivate, Philadelphia, United States of America).

Selection process
Two pairs of reviewers independently screened each title and abstract using the eligibility criteria. They read relevant full-text articles and systematically applied eligibility criteria. Disagreement was settled using a consensus approach between the two reviewers. Discrepancies were resolved by discussion or by a third senior researcher.

Data extraction and charting
Using the topics and questions presented in Box 1, we developed a data extraction and charting framework to map evidence about health system, providers, and patients' characteristics of rehabilitation care models for post COVID-19 condition. We categorized the extracted data using the topics and questions presented in Box 1.

Risk of bias assessment
We planned to conduct an assessment of risk of bias by two reviewers using the Cochrane Risk of Bias tool 29 on any included randomized controlled trials (RCTs) and nonrandomized controlled trials.

Data synthesis
We describe characteristics of the included studies (e.g. years, countries,

Systematic reviews
Rehabilitation care models for post COVID-19 condition Simon Décary et al.
population, type of care model) using simple descriptive statistics (frequency and percentage). We conducted a thematic content analysis centred on the five topics and signalling questions. We present a narrative synthesis of information and created a concept map of identified evidence.

Study selection
After duplicate removal, we identified 13 753 titles and abstracts (Fig. 1). We read 154 full texts and included 37 articles reporting information related to the five topics and 12 questions on rehabilitation care models. 17,

Characteristics of articles
Seven out of 37 included articles were published in 2020, 27 were published in 2021 and 3 were published in 2022 (Table 1). Sixteen articles were conducted in the United Kingdom of Great Britain and Northern Ireland. All but one of the studies were conducted in high-and uppermiddle-income countries. The number of participants per study ranged from 14 to 1325. No articles reported on children.

Topic 1: Components and functions of rehabilitation care models
Research question: (i) what are the core components and functions of rehabilitation care models?
We define a care model as the organizational structure required to deliver health services and interventions within a health system. We propose that care models rely on multiple possible active components required to support the delivery of services. Components also benefit from functions as mechanisms or tools to support the operationalization of the different components that constitute a care model. Complete definitions are available in the data repository. 25 We searched for description of the following components: patient-centred care and shared decision-making, patient education, guided selfmanagement (supported recovery), integrated care, multidisciplinary teams, shared care, continuity or coordination of care, case management, patient navigators, one-stop-shop clinics, asynchronous care, evidence-based care, community of practice, quality improvement, patient-reported outcome measures evaluation, training for health-care professionals or research partnership. We searched for description of the following functions: decision support for health care professionals, clinical information system, triage system, standardized symptoms assessment, social determinants assessment, referral system, follow-up system, patient support groups, home-based care, telehealth/virtual care.

Topic 2: Safe delivery of rehabilitation
Research question: (ii) to ensure safe rehabilitation, which COVID-19-related symptoms and conditions and/or complications (e.g. myocarditis, arrythmia, pulmonary emboli, severe desaturation) need further investigation and/or treatment and management before referral to general or specific rehabilitation interventions? Safe delivery of rehabilitation includes the identification of conditions or symptom clusters that need management before referral for rehabilitation.

Topic 3: Rehabilitation referral principles
Research questions: (iii) who should be referred for rehabilitation services and what would be relevant criteria for referral into rehabilitation?; and (iv) what is the proposed timing for referral into rehabilitation?
We define criteria for referral as the identification of relevant patient-level characteristics for referral into rehabilitation, regardless of the referral type. For example, criteria based on severity of symptoms, initial disease severity, overlap of symptom clusters, risk factors for development of persistent limitations in functioning, limitations in functioning assessed with a scale (e.g. Post COVID-19 functional status scale), abnormal clinical findings, outcome measures (impairment), patient-reported outcome measures (e.g. health-related quality of life), return to work or amenability to rehabilitation. We define timing for referral as the decision about when the optimal timing is for referral into rehabilitation, regardless of the referral type.

Topic 2
We identified three articles proposing symptoms that need further management. 17,30,31 The articles did not directly address access to rehabilitation, but screening for conditions that could be addressed either with a different referral or during the rehabilitation process.
One article proposed to screen for worsening breathlessness, the partial pressure of oxygen in the arterial blood below 96%, unexplained chest pain, new confusion or focal weakness. 17 One article proposed to screen using a cardiopulmonary exercise test. 30 One article proposed to refer people with post COVID-19 condition to the relevant acute services if they have signs or symptoms including orthostatic intolerance (e.g. palpitation or dizziness on standing), oxygen desaturation on exercise, signs of severe lung disease or cardiac chest pain. 31

Topic 3
We identified 16 articles reporting on rehabilitation referral principles. 17,[30][31][32]35,[37][38][39][40]44,54,55,58,60,62,63 Fifteen articles provided information on criteria for referral to rehabilitation. 17,[30][31][32]35,[37][38][39]44,54,55,58,60,62,63 The content analysis of each article is available in the data repository. 25 Eleven articles reported that the main criteria for referral into rehabilitation were based on any new or persistent symptoms from COVID-19. Six articles mentioned the importance of ruling out other diagnoses or urgent medical conditions and possible reinfection before referral into rehabilitation. Three articles additionally emphasized that symptoms should have an impact on functioning and quality of life to be eligible for referral. Two articles proposed the use of a standardized tool including referral criteria based on expert consensus (i.e. COVID-19 Yorkshire Rehabilitation Scale). 66 No article mentioned severity as a criterion for rehabilitation. All included articles valued a personalized testing and assessment procedure with no information of a core assessment procedure.
Eleven articles provided information on timing for referral to rehabilitation, 17,32,35,37,38,40,55,58,60,62,63 however, without considering the duration of 3 months from the onset of COVID-19. The content analysis of each article is available in the data repository. 25 Eight studies recommended immediate referral following hospitalization. For patients in the community, the timing for referral occurs following assessment from family physicians, nurses or other health-care workers, usually without strict temporal criteria. Three articles highlighted a self-referral and direct access process for timing of rehabilitation. Four studies recommended a waitand-see approach or self-management approach of at least 6 weeks following symptoms to observe possible natural recovery before referral to rehabilitation.
Some articles proposed a fixed 8-week or 12-week length of programme, while others proposed an individualized approach.

Topic 5
We identified 30 articles proposing health-care professionals to deliver rehabilitation services for post CO-VID-19 condition (Fig. 3). 17 32,43,47,55,60,61 We found no information concerning the type of competencies and skills nor the number of years of clinical experience required for working with post COVID-19 condition. Fig. 4 presents a concept map to guide decision-makers in designing sustainable rehabilitation care models for post COVID-19 condition.

Discussion
Here we provide current evidence on health system, providers and patients' characteristics for care models for post COVID-19 condition. Considering that the evidence retrieved is conceptual, expert based, with no high-quality trials, below we guide decision-makers on how to locally adapt rehabilitation services for post COVID-19 condition within their health systems and we provide key policy messages for decision-makers (Box 2). We also highlight the evidence gaps for researchers to answer.
Decision-makers need to consider that current care model proposals worldwide were developed based on expert opinions and may be linked to conflict of interest and biased perspectives (e.g. country of origin, professions). For example, most included articles come from high-to upper-middle-income countries. The proposed components and functions will probably face applicability issues within different health systems. For example, decision-makers in the United Kingdom were the first to propose a highly financed post-COVID clinics network organized at the national level. Although inspiring, the applicability to other health systems is unknown because of funding sustainability. Hence decision-makers need to locally adapt rehabilitation services for post COVID-19 condition within their health systems.
While a multidisciplinary team approach appeared as the most prevalent component of rehabilitation care models, articles reported only a few professions as key providers. Pivotal rehabilitation professions may be underrepresented in studies such as physiatrists, psychologists, speech and language therapists or dieticians. This potential underrepresentation in evidence also extends to the specifics of patients assessed within rehabilitation care models. The focus was mostly on a single body structure or function, rarely considering multiple impairments and limitations in functioning. Most articles reporting on patients' outcomes had a small sample Concepts of care models appear to spur from the current understanding of rehabilitation. 67 However, rehabilitation deals with complex interrelations of comorbidities with different courses (e.g. acute onset, progressive, episodic or relapsing remitting) for many conditions. Yet not one care model may be transferable to post COVID-19 condition. To create effective care models, we must disentangle components and functions that are specific to post COVID-19 condition, while leveraging effective practices used for other disabling conditions. Described components such as multiprofessional rehabilitation teams, continuity or coordination of care, or people-centred care, highlight the importance of interdisciplinary work and the involvement of patients regarding their preferred rehabilitation services and outcomes. Other components address education of patients and selfmanagement as integral parts of case management. The reported functions suggest a care model supported with a standardized monitoring system which allows referrals based on patient needs and an option of home-based care that may be delivered with telerehabilitation services. We argue that these components should be standard practice for rehabilitation of conditions with complex and chronic rehabilitation needs.

Fig. 2. Proposed components and functions of rehabilitation care models for post COVID-19 condition
A challenge in designing a care model for post COVID-19 condition is that it needs to consider people who gradually recover, people who experience episodic disability 68 and people who may be facing a permanent disability. 69 We can hypothesize that clinical experience in other chronic conditions, such as neurological diseases, cancer or cardiovascular diseases could yield superior patient outcomes by adapting indirect evidence for post COVID-19 condition patients.
Further research is needed as we found limited information to identify the optimal rehabilitation service delivery setting. Decision-makers could consider a hybrid delivery mode including face-to-face or virtual mode, but the evidence concerning its safety, effectiveness or non-inferiority to traditional delivery in an outpatient setting is still lacking. Integrating rehabilitation services at many different levels of health care from primary care to hospital-based care is probably feasible, but trials of rehabilitation care models and pathways are still lacking for post COVID-19 condition. We could not determine the ideal length of a rehabilitation programme. Limited information does not allows us to fully identify a core multidisciplinary team of health-care workers providing rehabilitation interventions for post COVID-19 condition. The nature of their professional implication is yet to be determined (e.g. number of sessions, intensity, exposure and interventions). Our concept map could help researchers to develop care model interventions to assess their impact and cost-effectiveness in RCTs.
We observed a scarcity of information concerning safe delivery of rehabilitation with the assessment of signs and symptoms that prevent the admission of a patient to rehabilitation, at least temporarily and when not medically managed. We found only a few articles describing signs and symptoms of the cardiovascular, cognitive and psychological domains that need further investigation and management without specifically mentioning the need for their management to ensure safe rehabilitation. Clinicians have already identified contraindications for physical activity interventions in post COVID-19 Table 2. Themes identified concerning rehabilitation service delivery settings for post COVID-19 condition

Fig. 4. Concept map for the design of a rehabilitation care model for post COVID-19 condition
A few articles described cardiovascular, cognitive and psychological signs and symptoms that need further investigation and management, to be adressed either with a different referral or during the rehabilitation process. More research is needed.

WHEN ?
Topic 3b. Timing for referral to rehabilitation

Competencies and skills
No information found on competencies and skills needed.

Clinical experience
No information found on the number of years of clincial experience needed.

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Rehabilitation care models for post COVID-19 condition Simon Décary et al.
condition, such as cardiac impairment following COVID-19 and post-exertional symptom exacerbation. 70 Authors of all articles recommended personalized assessments, which included detailed history of the disease, clinical examination, activity tolerance (e.g. physical or cognitive) and impact of symptoms on functioning, but no article considered standardized assessment of conditions that prevent safe delivery of rehabilitation. This lack of information may be driven by underreporting of potential negative consequences such as adverse events and harms in rehabilitation studies. Suboptimal reporting of harms and adverse events is an ongoing issue in randomized trials and rehabilitation studies. 71 Future research on rehabilitation for post COVID-19 condition should identify prevalence of harms and adverse events during and after rehabilitation to guide standardized safety netting within care models.
As the pandemic evolves into endemicity, more people will develop post COVID-19 condition each year for the foreseeable future, even with vaccine protection. 72 We have gathered four key policy messages for decisionmakers and researchers for developing and improving rehabilitation care for people living with post COVID-19 conditions (Box 2). We suggest a multilevel and multiprofessional model, where decision-makers should leverage all available strengths and experiences of their own health system to provide rehabilitation services by funding programmes and research that aim for optimal rehabilitation outcomes. We also suggest providing guidance for researchers and clinicians to develop and adopt appropriate mechanisms to increase patient safety. Decision-makers can use our concept map, keeping in mind the current state of evidence, to design potentially effective, locally adapted and sustainable rehabilitation care models for post COVID-19 condition. 